NoVEiVIBER 14, 1 901] 



NA TURE 



29 



Shell Life : an Introduction to the Bj-itish Molliisca. By 



E. Step, F.L.S., &c. "Library of Natural History 

 Romance." Pp. 414, 32 Plates, Figs, in text. (London : 



F. Warne and Co., 1901.) Price bs. 



Coui.n paper, print and pictures make a meritorious 

 book, this would be one. The paper is of superior quality, 

 and the print is exceptionally clear and clean ; whilst the 

 illustrations, although drawn from many sources, good, 

 bad and indifferent, are well printed. 



The thirty-two photo-process plates are excellent of 

 their kind, their only fault consisting in the want of good 

 arrangement m their component items and the inclusion 

 of some objects far too minute for this method of illus- 

 tration. Unfortunately there is no reference to them in 

 the text, and the names cited on the plates do not always 

 coincide with those given in the text. 



The figures in the text are some of them very old 

 friends, and saw service in the Rev. J. G. Wood's 

 "Common Shells of the Sea-shore"; others are of later 

 date and foreign extraction. Nor must we omit a word 

 of praise for the binding and the tasteful and quaint, if 

 not entirely appropriate, design on the cover. 



It is a matter for regret, however, that the author did 

 not make himself more familiar with his subject so that 

 his work might have been something better than the mere 

 outcome of industrious compilation from authorities more 

 or less ancient. Thus he instances the patelliform as the 

 primitive type of the molluscan shell ; he is unaware of 

 the existence of a rudimentary heart in Dentalium, and 

 gives renewed currency to the blunder (founded originally 

 on a mistranslation) that its embryo shell is bivalve ; and 

 so on, and so on. 



In the matter of classification our author follows that 

 of the Cambridge Natural History, which, having already 

 been dealt with in these pages (vol. lii. p. 150), need not 

 be further commented on here ; nor shall words be wasted 

 on the nomenclature employed, which is hopelessly out 

 of date. 



In the endeavour to confine scientific names entirely 

 within brackets and furnish " popular " names where 

 none such exist, the author is driven to translations, some 

 of which recall those that once figured on the fossil fish 

 tablets in the British Museum. As a rule derivations of 

 names are, perhaps wisely, avoided ; but we do meet 

 with " Aplysia (from a and plus, unwashable)." 



On the whole we incline to the opinion that the pub- 

 lishers did well to include this book in their " Library of 

 Natural History Romance." (BV)-. 



Arithmetic. By R. Hargreaves, M.A. Pp. viii-l-416. 

 (Oxford : Clarendon Press, 1901.) Price 45. bd. 



Lr is very difficult for an author to produce anything 

 strikingly new in such a well-worn subject as arithmetic, 

 and consequently this treatise greatly resembles two or 

 three others of the most meritorious character. A good 

 feature of the work is the attention which it devotes to 

 the theory of arithmetic. Labour-saving processes, 

 when long multiplications have to be performed and one 

 of the factors possesses some particular simplicity of 

 form, are frequently given — to the interest as well as to 

 the advantage of the pupil. 



If only our terrible system of weights and measures 

 were replaced by the metric system, what a load of re- 

 volting and time wasting work would be removed from 

 the path of the English pupil ! A short account of this 

 system will be found in the present work. 



Perhaps the explanation of the properties of recurring 

 decimals is scarcely so complete and systematic as it 

 might be. Here the use of a little algebra would do a 

 great deal towards promoting in the mind of the pupil an 

 understanding of the various rules for treating these 

 decimals ; and there seems to be no valid reason against 



NO. 1672, VOL. 65] 



the employment of algebra for such a purpose. Purely 

 arithmetical proofs necessarily fail in generality. 



There is a good section on approximative work which 

 will be a great help to the learner. There are also sec- 

 tions on the square and cube root ; but, with a logarithm 

 book in our hands, the utility of arithmetical or alge- 

 braical processes for finding a cube root is more than 

 doubtful. 



The work abounds with examples, and with good hints 

 to the pupil for shortening calculation and for choosing 

 one mode of procedure in preference to another when 

 two or more ways of doing a thing present themselves. 



Intermediate Practical Physics. By J. B. Wilkinson. 



Pp. X -1-154. (London : Chapman and Hall, Ltd., 



1902.) Price 2s. bd. 

 This book is for the intermediate and preliminary 

 scientific examinations of the London University, and 

 deals with experiments of a very simple kind. The 

 exercises illustrate the various branches of physics, and 

 they seem to be very suitable for beginners ; but we regret 

 that in many cases the descriptions are not accurate. 

 Thus, in describing the measurement of the diameter of 

 a sphere by placing it between two squared blocks, we are 

 told to test the right-angles of the blocks by seeing 

 whether they fit when placed on the table and then turn- 

 ing both blocks over. Surely this is no test. A little 

 further on, in the account of the siphon barometer, the 

 correction for change in density of the inercury and the 

 expansion of the glass scale is attempted, but sadly needs 

 revision and rearrangement. We should also like to 

 know why the corrections for temperature are given with 

 the siphon barometer and not with Fortin's pattern, where 

 they must be equally important. Although many other 

 points in the book require some correction, we think it is 

 written on the right lines, as it aims at simplicity. 



S. S. 



Flowers of the Field. By the late Rev. C. A. Johns. 

 29th edition. Entirely rewritten and revised by 

 G. S. Boulger, B.A., F.L.S., F.G.S., Professor of 

 Botany in the City of London College. Pp. xlii -f- 

 926. (London : Society for Promoting Christian 

 Knowledge, 1899.) 

 The fact that this work should have passed through so 

 many editions sufficiently proves its popularity. The 

 present \olu.Tie is an improvement on its predecessors, 

 both by reason of the inclusion of new and valuable 

 matter and by the excision of some that could be very 

 well spared. The more definite and full descriptions of 

 the species should aid in the identification of our British 

 plants, but the illustrations still are capable of improve- 

 ment. The book is, however, sure of a wide circulation 

 amongst the large number of people who take an interest 

 in, and desire a closer acquaintance with, the wild flowers 

 of the country. 



Co>-relation Tables of British Strata. By Bernard 

 Hobson, M.Sc, F.G.S. (London : Dulau and Co., 

 1901.) Price 5J. 

 A SHORT time ago (Nature, April 11) attention was 

 called to the publication of Woodward's " Table of 

 British Strata," also issued by Messrs. Dulau and Co. The 

 present work is in some respects far more elaborate, as it 

 comprises nineteen detailed tables ranging from Archaean 

 to Pleistocene. The plan of the compiler is to give the 

 subdivisions of each formation as determined in diflTerent 

 regions in Great Britain and Ireland. Thus, to take the 

 Cambrian, there are columns for North Wales, South 

 Wales, Malvern Hills, Wrekin area, Nuneaton, North- 

 west Scotland, and Ireland ; and in these columns the 

 various local divisions and their estimated thicknesses 

 are given, together with references to original sources of 

 information. No attempt is made 10 enumerate the 



